uniform sampler2D m_Texture;
varying vec2 texCoord;
 
void main() {
    vec4 texVal = texture2D(m_Texture, texCoord);
    //float g = ma*(te*Val.r,ma*(te*Val.g,te*Val.b));
    gl_FragColor.r = (texVal.r * 0.393 + texVal.g * 0.769 + texVal.b * 0.189);
    gl_FragColor.g = (texVal.r * 0.349 + texVal.g * 0.686 + texVal.b * 0.168);
    gl_FragColor.b = (texVal.r * 0.272 + texVal.g * 0.534 + texVal.b * 0.131);    
}